Under the flooring on second floor

[Greygon]

I was looking under our second floor flooring and discovered these two cables/wires. They're is electrical nearby to a light fixture but are these electrical too! Or something for stability?

[Greygon]

Sorry these are the cables/wires I am talking about. In the one photo you can see the electrical wire below it. These wired are thinner than the electrical.

[Olson185]

I'm only seeing the two wires used in a Knob & Tube system. Are you suggesting one is an electrical wire and the other is something else?

[Mick_VT]

That is indeed old knob and tube wiring

[Greygon]

Thanks. Now that I look it up, that is indeed what it appears to be. The electrical wiring for the fixture there does not feed off of that wiring.

A lot of work was done a few years ago to add in a second power panel. Also 220 outlets were added upstairs on these same rooms. I am hoping the k&t is just remnant and not active. Kind of afraid to check.

[1918ColonialRevival]

It's a standard K&T installation. One wire is hot and the other is neutral. There's a simple tool available at most hardware stores that will light up when placed next to a live wire. That will tell you if it's live. I recommend every owner of a house that's had at least two previous owners have one.

If it hasn't been modified, it's likely ok. K&T gets a bad rap from insurance companies, but much of that is Chicken Little syndrome. Since it goes across the ceiling, it's probably a feed for an overhead fixture(s). Even if it were still in use, overhead fixtures do not pull enough current to overheat the wiring.

It's when people overload an existing K&T circuit by adding onto it or stuff blow-in insulation around the wires that are designed to dissipate heat in the open cavity that it can cause trouble.

[Greygon]

It's a standard K&T installation. One wire is hot and the other is neutral. There's a simple tool available at most hardware stores that will light up when placed next to a live wire. That will tell you if it's live. I recommend every owner of a house that's had at least two previous owners have one.

The non-contact voltage detector. I spent some time digging last night and that is the method a couple of electricians also recommended. Luckily, I have at least one!!

Something I hadn't really considered when our journey to buy this home begun was the difficulty in obtaining insurance. I don't know if others have experienced it or not, but when we talked to our insurance company, they had a long list of questions/concerns about the age of the home. As I checked with various companies, the answer kept coming back, "We can't insure a home that old." Thankfully, one agent was able to provide coverage and it is a major insurer... But many kept saying that the rules in Alabama changed after the tornadoes in 2010/11 and they wouldn't insure a home older than 1930(?)....

Thanks for all the help! This forum has been awesome in helping me think through some things!!

[phil]

if there is more than one kind of wire maybe the K and T isn't live. 220 would require at least two hot wires. I dont' know why they ran the 220 but maybe they did something funny there? It's usually just used for stoves, heaters, dryers etc. and those should be on a separate line from your outlets. It sounds like it wouldn't hurt to have an electrician check it out and make recommendations even if you do the work. You could look around your panel and see if you have a bunch of romex running into the panel or you have a bunch of K and T being fed by the panel. That still won't tell you if the K and T might be partially or completely live but it's possible it has been taken out of commission. The K and T is usually fed through the porcelain insulators. you could also find other wires perhaps from phone doorbell old antennas etc but that will be different wire.

be careful with neutrals. they may appear dead to your tester until you use the circuit and then they are part of a return path for the current. don't think of those wires as grounds, they are not. K and t wiring has no ground usually. the outlets should not have a ground. ( sometimes people cheat and install grounded outlets with no actual ground connection.)

in addition to the current tester you should buy an outlet tester. you just plug it into any (grounded) 110V outlet and it'll show if its wired incorrectly and they are only about 10 bucks. you'll find one locally but here's an example:

http://www.itm.com/product/extech-et15- ... AlQU8P8HAQ

If it is K and T yes that will affect your insurance and some companies may not carry you. a good electrician may be able to have a look around and advise how to make sure it's safe. If it's still on K and T it's probably best to rewire but it can be a large job and the most important thing is that it's safe. Contractors and previous owners can do some strange and dangerous wiring and if it were me I'd look into it further so you can make sure it's safe for now and perhaps plan to do future upgrades in a manor that allows you to still have power to live in it.

in particular you should find out why they would have run 220 to bedrooms. maybe someone did something funny to connect a heater? or something?

[Greygon]

The 220 to the rooms is all at the window -- they appear to have been added for window a/c units. I don't see any K&T into either panel box, but then they could have run romex out of the panel and then re-energized the k&t away. I am going to check the k&t lines I found to see if they are hot now that I know how. I just wasn't sure how (although I own one of the non-contact testers because I use it every time I touch a wire because I am that cautious around electricity). The k&t threw me and I wasn't sure if testing it that way worked. I also discovered a Mr. Electric card taped behind the box, hoping they did some of the wiring and assessed the rest and maybe will have job history.

[Greygon]

Testing complete and the verdict is...hot k&t... The condition of the wires that I can see is pretty good. Surely the wires that I can't see are in even better condition... right. :/